Optical detectors and focal plane arrays are presently used in a number of industries to capture light for analysis. Presently, there is a great deal of interest in producing optical detectors and focal plane arrays with higher sensitivity to incident light while decreasing the noise produced within the detector or focal plane array.
One class of device currently in use comprises a photodetection device having an active detection area which is matched to an optical readout chip. During manufacture, great care must be taken when coupling the readout chip to the photodetection device. Typically, the photodetection device and the readout chip are positioned within a high vacuum chamber and the contact surfaces of each device are cleaned to ensure the surfaces are free of molecular contaminants. Thereafter, a bonding agent may be applied to a surface of at least one of the photodetection device and/or the readout chip, thereby bonded the photodetection device and readout chip together. Typically, these devices are referred to as “flip-chip” devices. While these devices have proven useful in detecting incident radiation, a number of shortcoming have been identified.
During use, imaging information is derived by knowing precisely which pixel of the active detection area of the photodetection device generated an electrical signal within the readout chip. Since pixel sizes are quite small, it is imperative that the non-conducting and conducting regions of the photodetection device and readout chip overlap and maintain their position relative to each other during the manufacturing process. Typically, the manufacturing process incorporates extensive procedures to align and register the photodetection device and readout chip. As such, manufacturing yields are not high. Furthermore, the manufacturing process is quite lengthy, labor intensive, and costly.
Thus, in light of the foregoing, there is an ongoing need for a self-pixelating focal plane array which can be produced more efficiently.